Symptoms of a Bad Spark Plug Wire:

What Are Spark Plug Wires?

Spark plug wires, often called ignition wires, carry electricity from the ignition coils to the spark plugs in many car and truck engines. Over time they can begin to wear or short out, potentially leaving them unable to carry enough charge to create a spark. Because of this, the symptoms of a bad or faulty spark plug wire set can be very similar to the symptoms of a fouled spark plug.

It is important that a vehicle’s spark plug wires be inspected at regular intervals, and replaced during tune-ups. In modern vehicles, coil-on-plug ignition is now often being used, eliminating the need for spark plug wires. Refer to your owner’s manual for vehicle specifications and maintenance schedule.